Do you think Dubai police are unfair with cars having Abu Dhabi registration plates?

i heard a lot about this kind of prejudice, which i thought was ridiculous. this was till last weekend, I had to travel via Dubai Airport, and we received a parking ticket even when we were still in the car! it was a white and black colored pavement, and technically the car was not parked, driver was in and it was moving slowly when the officer insisted on issuing the ticket! He even threatened to withdraw the driver's license upon our objection. Is it just another person in power misusing his authority or was it the Abu Dhabi plate that got us in trouble.